<!DOCTYPE html>
<html>
<head>
  <title>Hello World</title>
</head>
<body>

<h1>Đây là một trang web</h1>

<a href="/about">About</a>

<form method="get" action="/hello">
  <input type="input" name="name">
  <button type="submit">Submit</button>
</form>
</body>
</html>